Cui, I wouldn’t call font stacks complicated — they all boil down to either ‘serif’ or ‘sans-serif’.

I just think that all the legal meters of embedded fonts are in contradiction with the openness of the web. Browsers shouldn’t contain permission tables of copyrighted work which can or cannot be rendered, nor should it ping font author’s servers.

I called font stack “sophisticated” since you need some serious study to elaborated them :
* compare font rendering on various OS
* take care of fonts presence’ probability on those plateform

Then, another step is necessary : be aware of the problem of font compatibility !
Yes, every _real_ webdesigner should ! But it would be interesting to measure what percentage of WP themes (for example) use complete font stack (not just « font-family : Arial, Sans serif »).

The problem of openness is a different matter.
First, the way to handle font licensing is not technically solved/decided yet.

Then, the present way to use specific fonts in web design is (generally) to convert text to image (dynamicly, or not), and without taking into account any licencing matter, just like when you publish a photograph : copyrigths may have been respected. Or not.

I’m not (at all) a pro webdesigner, but just like PDF, I think that having a page rendering stable regardless of OS and browsers is a valuable goal.